Shooting at a subway station in New York City
Shooting at a subway station in New York CityREUTERS/Brendan McDermid

A federal grand jury in Brooklyn on Saturday returned a two-count indictment against alleged subway shooter Frank James, ABC News reported.

The indictment expands the charges James is facing for allegedly shooting 10 people on a Manhattan-bound N train on April 12. No one was killed.

James is now charged with carrying out a terror attack against a mass transit system and discharging a firearm during a crime of violence, according to ABC News.

If convicted of the terror charge, he faces up to life in prison. The second charge also carries the possibility of a life sentence.

No date has been set for his arraignment.

James was arrested in Manhattan a day after subway attack, after calling a police tip line to say where he was.

Authorities say he unleashed smoke bombs and dozens of bullets in a train full of morning commuters.

James did not enter a plea in his first court appearance on April 14. Following the appearance, his lawyer, Mia Eisner-Grynberg, called the shooting a tragedy but said that initial information can often be wrong. She also lauded James for turning himself in.

James is being held without bail. A motive for the attack remains unclear.